This invention relates to an electrophotographic photoreceptor and preparation thereof, and more especially a charge generating layer of a photoreceptor comprising an evaporated film of chloroaluminium phthalocyanine and chloroaluminium monochlorophthalocyanine and providing for a treatment of an organic solvent and having a high sensitivity of near infrared region especially over 750 nM of wavelength. In the prior art of an electrophotographic photoreceptor, it is common to form a mono layer as a photosensitive layer on electrical conductive plate, for example, amorphous selenium, lead oxide, cadmium sulfide in inorganic compounds, and poly vinyl carbazole--trinitrofluorenone, pyrylium salt--triphenylmethane in organic compounds. On the other hand it has been already known that an electrophotographic photoreceptor comprising an electrode, a charge generating layer and a charge transport layer is invented. About a wavelength region of photosensitivity, former photoreceptors exclusive of the photoreceptor of metal phthalocyanines have photosensitivity in from the ultraviolet region to the visible region and reduces photosensitivity in region of near infrared, especially over 700 nM of wavelength. Accordingly, it has been investigated that various methods of sensitization are tried to obtain the photoreceptor having an excellent photosensitivity in near infrared region. For example, cadmium sulfide and lead dioxide are sensitized to add coloring agents and selenium are sensitized to add tellurium. In these cases, however, the photosensitivity of the photoreceptor reduce remarkably in region of near infrared, especially over 750 nM of wavelength. It is doubtful that the use of coloring agents as the sensitizer is unsatisfactory because of their chemical durability and also because of the physical, electrical durability of the photoreceptor in the sensitization by tellurium. On the other hand, the use of metal phthalocyanines in electrophotographic photoreceptor is well known. For example, U.S. Pat. No. 4,181,772 which discloses an adhesive generator overcoated photoreceptor therein as generating pigment metal phthalocyanine and metal-free phthalocyanine, U.S. Pat. No. 4,214,907 which discloses photosensitive material for electrophotography having a polyvinylcarbazole derivative, phthalocyanine and an electron-acceptor, British Pat. No. 1268422, which discloses phthalocyanine composition and method of preparation and UK Patent application GB No. 2023298A which discloses electrophotographic material and method therein, charge generating materials dispersed in polymer are X metal-free phthalocyanine, metal phthalocyanine, vanadyl phthalocyanine are dispersed in a polymer. However, the prior art does not indicate that the photoreceptor using metal-free phthalocyanine or metal phthalocyanine has a high photosensitivity in the near infrared region. Also it is well known that the peak of photosensitivity lies in range of wavelength from about 700 to about 800 nM in metal-free phthalocyanine, metal phthalocyanine and is gradually reduced in wavelengths longer than 750 nM. In the present invention relating to an electrophotographic photoreceptor comprising an electrically conductive substrate, a layer of charge generating material and a layer of charge transport material, it has been found that the absorption peak of chloroaluminium phthalocyanine and chloroaluminium monochlorophthalocyanine evaporated film shift from short wavelength to long wavelength with treatment by an organic solvent. The present invention provides an electrophotographic photoreceptor which has a high photosensitivity in regions of near infrared, especially over 750 nM. The region of near infrared are a stable emission region of semiconductor laser diode as well known.